Resumen de Ventilatory Breakpoints in Boys and Men

Panagiota Klentrou, Mary Lou Nishio, Michael Plyley

• The purpose of this study was to compare the ventilatory breakpoints during exercise between young boys and adult men. Twenty-four active volunteers, 12 boys (10.8 ± 0.3 years of age) and 12 men (24.6 ± 1.1 years of age) with similar aerobic power (53.6 ± 4.2 to 55.7 ± 3.5 ml×kg¿1×min¿1), participated in the study. Each participant completed a standardized Physical Activity Questionnaire and anthropometric variables were measured. The exercise testing consisted of two graded tests to exhaustion on a treadmill. Heart rates were recorded every minute and gas exchange parameters were obtained every 30 s throughout the tests. Each ventilatory breakpoint was determined using a three-part model. Although the relative VO2peak values were not significantly different between the boys and the young adults, the boys reported significantly (p = .05) higher total activity than the adults. The boys had a significantly higher (p = .05) first ventilatory breakpoint expressed as a percentage of VO2peak than the adults (64.9% vs. 57.7%). Only 50% of the boys demonstrated a discernable VB2, and the VB2 of this group was not significantly different from that of the adults.